JP6657619B2 - Molded body - Google Patents

Description

  The present invention relates to a molded article.

  Acrylic resins represented by polymethyl methacrylate (PMMA) have high transparency, and are used in the fields of optical materials, vehicle parts, building materials, lenses, household goods, OA equipment, lighting equipment, and the like. Widely used. In particular, in recent years, applications to vehicles, light guide plates, films for liquid crystal displays, and the like have been advanced. However, with known acrylic resins, antifouling properties and scratch resistance may become a problem depending on the application.

  For example, in the case of a molded article for a vehicle exterior, anti-scratch performance when the molded article is assembled to a vehicle body and anti-scratch performance when the vehicle is washed are required. In sanitary applications such as washbasins and toilet bowls, replacement of pottery with acrylic resin, which is lighter and has good appearance quality, is progressing, but antifouling properties and abrasion resistance have been issues.

  As a method for improving the scratch resistance and antifouling property of an acrylic resin molded product, a method of coating the surface of the molded product in a separate step is known. Examples of a method for improving the scratch resistance of an acrylic resin molded product include, for example, a method of hard coating with a coating liquid containing a UV-curable polyfunctional acrylic resin as a main component (for example, Patent Document 1), and a method of hard coating. A method of insert-molding a coated film and the like (for example, Patent Document 2). Further, as a method for improving the antifouling property of the acrylic resin molded product, a method of adding a silicone-based or fluorine-based additive to a hard coat (for example, Patent Document 1), a method of adding a fluorine-based antifouling coating to a molded article, (For example, Patent Document 3).

JP 2008-138165 A JP 2011-126921 A JP-A-10-7950

  However, as described in Patent Documents 1 to 3, a method of forming a coating layer by applying a coating to an acrylic resin molded body in a separate step is disadvantageous in terms of cost. When the acrylic resin molded article is used as it is as a product after molding, it is required to have good scratch resistance and transparency.

  An object of the present invention is to provide a molded article having good scratch resistance and excellent transparency.

  The present invention is the following [1] to [5].

[1] A molded product made of an acrylic resin molding material containing a polymer (X) containing methyl methacrylate as a monomer unit in an amount exceeding 80% by mass,
Without having a coating layer having a thickness of 1 μm or more on the surface of the molded body,
When a reciprocating friction test was performed using a cotton cloth as a slider at a constant load of 2.45 N (250 gf) on the surface of the molded body, the maximum value of the coefficient of dynamic friction was 0.4 or less within the range of 10 to 400 reciprocations. And a molded article having an internal haze value of 2.5% or less.

[2] The molded article according to [1], wherein the surface of the molded article has a Martens hardness of 140 to 250 N / mm ² .

  [3] The molded article according to [1] or [2], wherein the acrylic resin molding material has a Vicat softening temperature of 108 ° C or higher.

  [4] The molded article according to any one of [1] to [3], wherein the arithmetic average roughness Ra of the surface of the molded article is 5.0 or less.

  [5] The acrylic resin molding material contains, as a monomer unit, a polymer (Y) containing methyl methacrylate and an alkyl (meth) acrylate having an alkyl group having 8 to 30 carbon atoms [1] ] The molded article according to any one of [4] to [4].

  According to the present invention, it is possible to provide a molded article having good scratch resistance and excellent transparency.

  Hereinafter, a mode for carrying out the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail, but the present invention is not limited to the following description, and various forms are included within the scope of the gist. It can be modified and implemented.

  In the following, the monomer component before polymerization is referred to as “-monomer”, and the “monomer” may be omitted. In addition, the structural unit constituting the polymer is referred to as “-monomer unit”. Further, (meth) acrylate indicates methacrylate or acrylate.

[Molded body]
The molded article according to the present invention is made of an acrylic resin molding material containing a polymer (X) containing methyl methacrylate as a monomer unit in an amount of more than 80% by mass. The surface of the molded body does not have a coating layer having a thickness of 1 μm or more. When a reciprocating friction test was performed on the surface of the molded body using a cotton cloth as a slider under a constant load of 2.45 N (250 gf), the maximum value of the dynamic friction coefficient was 0.4 or less within the range of 10 to 400 reciprocations. . The molded article has an internal haze value of 2.5% or less.

  The molded article does not have a coating layer having a thickness of 1 μm or more on its surface. Here, the “coating layer” refers to a film formed on the surface of the molded body, which is made of a material different from that of the molded body. For example, the molded article is obtained by laminating a molded article obtained by thermoforming an acrylic plate having a coating layer, a molded article having a coating layer disposed on a surface in a separate step, a film having a film, and the like. Does not include Generally, in order to impart abrasion resistance with a coating layer, the thickness of the coating layer needs to be 1 μm or more. On the other hand, those in which some of the additives contained in the acrylic resin molding material segregate, bleed, or ooze out on the surface of the molded article after molding are included in the molded article according to the present invention. Examples of the coating layer include a hard coat formed by curing an active energy ray-curable resin composition.

[Dynamic friction coefficient]
In the present invention, the dynamic friction coefficient is a value obtained by a reciprocating friction test described later. The dynamic friction coefficient measured in the reciprocating friction test made it possible to accurately quantify the scratch resistance in an actual use environment. Specifically, in the method of measuring the dynamic friction coefficient using a metal or resin slider, the material is significantly different from clothing and the like that are expected to come into contact in an actual use environment, and when the contact is repeated. Was unable to capture the change in the frictional state. In the present invention, a molded article having excellent scratch resistance has been specified based on the dynamic friction coefficient measured by the reciprocating friction test method newly discovered.

  That is, in the reciprocating friction test according to the present invention, it has been found that when the maximum value of the dynamic friction coefficient is in the region of 0.4 or less, excellent scratch resistance can be exhibited in an actual use environment. The lower the coefficient of kinetic friction, the higher the slipperiness of the surface and the less likely it is to be scratched. The maximum value of the coefficient of dynamic friction is preferably 0.35 or less, more preferably 0.3 or less, and even more preferably 0.25 or less.

[Internal haze]
In the present invention, the internal haze is a value measured by a method described later. The internal haze value of the molded article according to the present invention is 2.5% or less, preferably 1.0% or less, more preferably 0.5% or less, and even more preferably 0.3% or less. A molded product having excellent transparency is obtained when the internal haze value is low. When the molded article has excellent transparency, the molded article can be used for optical components including a light guide such as a light guide, a lamp cover, and a light guide plate. In addition, since the molded article has excellent transparency, the coloring property at the time of coloring is also good, so that coloring by painting or dyeing in a separate step is not required, and good coloring property is realized with a small amount of pigment. be able to. For example, in order to achieve a glossy black color called piano black, it is effective to combine a material with a low internal haze value and high transparency with a black pigment. It is possible to obtain a high-quality piano black-like molded product.

[Martens hardness]
In the present invention, the Martens hardness is a value measured by a method described later. The Martens hardness measured by the method represents the hardness of the surface of the molded body, and serves as an index for determining whether or not a mark remains as a dent when a hard object comes into contact with the surface of the molded body. Martens hardness of the surface of the molded body according to the present invention is preferably 140~250N / mm ^2, more preferably 160~230N / mm ^2, more preferably 170~210N / mm ^2. When the Martens hardness is 140 N / mm ² or more, it is possible to prevent a phenomenon that the surface of the molded article is too soft and easily damaged. Further, when the Martens hardness is 250 N / mm ² or less, it is possible to prevent a phenomenon in which the surface of the formed body is hard and brittle and easily damaged.

[Vicat softening temperature (VST)]
In the present invention, the Vicat softening temperature is a value measured by a method described later. The Vicat softening temperature is an index indicating the heat-resistant deformation temperature of the acrylic resin molding material. The Vicat softening temperature of the acrylic resin molding material according to the present invention is preferably 108 ° C. or higher, more preferably 110 ° C. or higher, even more preferably 112 ° C. or higher. If the Vicat softening temperature is at least 108 ° C., it can be handled as a material having a heat resistant deformation temperature equivalent to that of PMMA. The upper limit of the Vicat softening temperature is not particularly limited.

[Arithmetic average roughness Ra]
In the present invention, the arithmetic average roughness Ra is a value measured by a method described later. The molded article according to the present invention preferably has a smooth surface. Those having a smooth surface and a substantially mirror-like gloss or gloss exhibit a high-grade appearance and good color developability, which are characteristics of a molded article made of an acrylic resin molding material. The arithmetic average roughness Ra is an index indicating the smoothness of the surface of the molded body. The arithmetic average roughness Ra of the surface of the molded article according to the present invention is preferably 5.0 or less, more preferably 3.0 or less, and even more preferably 1.0 or less. When the arithmetic average roughness Ra is 5.0 or less, a high-grade appearance of the molded article and good coloring properties are exhibited. The lower limit of the arithmetic average roughness Ra is not particularly limited.

[Polymer (X)]
The acrylic resin molding material according to the present invention contains a polymer (X). The polymer (X) contains methyl methacrylate as a monomer unit in an amount exceeding 80% by mass, and may contain another monomer (x1).

  The other monomer (x1) is a monomer other than methyl methacrylate, and is not particularly limited as long as it has copolymerizability with methyl methacrylate. Is preferably a monofunctional acrylate. Depolymerization reaction (zipper cleavage) of polymethyl methacrylate can be prevented by copolymerizing methyl methacrylate with monofunctional acrylate. Examples of the monomer (x1) include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, and the like. Among these, methyl acrylate is preferable from the balance between heat resistance and cost. These may be used alone or in combination of two or more.

  The amount of methyl methacrylate as a monomer unit contained in the polymer (X) is more than 80% by mass, preferably 85 to 100% by mass, more preferably 90 to 99.5% by mass, and more preferably 95 to 99% by mass. Is more preferred. The amount of the other monomer (x1) as a monomer unit contained in the polymer (X) is preferably 0 to 20% by mass, more preferably 0 to 15% by mass, and 0.5 to 10% by mass. The following is more preferable, and 1 to 5% by mass is particularly preferable. When the content of each monomer unit satisfies the above range, the molded article can exhibit sufficient heat resistance, weather resistance, heat decomposition resistance, transparency, mechanical properties, and the like.

  The weight average molecular weight (Mw) of the polymer (X) is preferably from 50,000 to 200,000, more preferably from 60,000 to 150,000, and from 70,000 to 100,000. Is more preferred. When the Mw satisfies the above range, the molded article can exhibit sufficient heat resistance, weather resistance, thermal decomposition resistance, transparency, mechanical properties, fluidity, moldability, and the like. Further, the number average molecular weight (Mn) of the polymer (X) is preferably 25,000 to 200,000, more preferably 30,000 to 150,000, and 35,000 to 100,000. Is more preferable. When the Mn satisfies the above range, the molded article can exhibit sufficient heat resistance, weather resistance, thermal decomposition resistance, transparency, mechanical properties, fluidity, moldability, and the like. Further, Mw / Mn is preferably from 1.0 to 2.0. Note that Mw and Mn are values measured by a method described later.

  As a method for producing the polymer (X), a known method such as a solution polymerization method, a bulk polymerization method, a suspension polymerization method, an emulsion polymerization method, and a precipitation polymerization method can be used. Among these methods, the bulk polymerization method and the suspension polymerization method are preferable, and the bulk polymerization method is more preferable. The bulk polymerization method is suitable for mass production, and is advantageous in terms of production speed (production amount), production cost, and the like.

  The ratio of the polymer (X) contained in the acrylic resin molding material is preferably 51 to 99 parts by mass, and more preferably 60 to 99 parts by mass with respect to 100 parts by mass of the polymer (X) and the polymer (Y) described later. 98 parts by mass is more preferable, and 70 to 95 parts by mass is further preferable. When the proportion is within the above range, stain resistance and scratch resistance can be imparted while maintaining the properties of PMMA.

[Polymer (Y)]
The acrylic resin molding material according to the present invention can contain a polymer (Y) other than the polymer (X) as a modifier for the polymer (X). The polymer (Y) has, as monomer units, methyl methacrylate and an alkyl (meth) acrylate having an alkyl group having 8 to 30 carbon atoms (hereinafter, referred to as a long-chain alkyl (meth) acrylate (y1)). And The polymer (Y) may contain a macromonomer (y2) and another monomer (y3) as a monomer unit.

  Methyl methacrylate contained in the polymer (Y) as a monomer unit plays a role in ensuring compatibility with the polymer (X). The amount of methyl methacrylate as a monomer unit contained in the polymer (Y) is preferably 51 to 99% by mass, more preferably 60 to 90% by mass, and still more preferably 70 to 90% by mass. When the amount of methyl methacrylate as a monomer unit contained in the polymer (Y) is 51% by mass or more, compatibility with the polymer (X) is sufficiently ensured, and the phase separation size is sufficiently reduced. In addition, the molded article can maintain sufficient transparency. The amount of methyl methacrylate as a monomer unit contained in the polymer (Y) includes methyl methacrylate derived from a macromonomer (y2) described later. Further, the amount of methyl methacrylate as a monomer unit contained in the polymer (Y) depends on the degree of influence of the long-chain alkyl (meth) acrylate (y1) on the compatibility with the polymer (X). It is adjusted appropriately.

(Long-chain alkyl (meth) acrylate (y1))
The long-chain alkyl (meth) acrylate (y1) has a function of modifying the surface of the molded article. When the polymer (Y) contains the long-chain alkyl (meth) acrylate (y1) as a monomer unit, the surface of the molded product exhibits a high water contact angle, and the antifouling property and the abrasion resistance are improved. The long-chain alkyl group having 8 to 30 carbon atoms in the long-chain alkyl (meth) acrylate (y1) may be linear or branched, or a mixture of both. However, a straight chain is preferred from the viewpoint of imparting a surface with slipperiness that contributes to improvement in scratch resistance. The long-chain alkyl group may be either saturated or unsaturated, or a mixture of both. Saturation tends to have better compatibility with the polymer (X), but unsaturated tends to have better transparency in a low temperature region because of lower crystallinity. The carbon number of the long-chain alkyl group is 8 or more and 30 or less, preferably 10 or more and 24 or less, more preferably 11 or more and 22 or less, and still more preferably 12 or more and 18 or less. When the carbon number is 8 or more, the water contact angle is improved, and when the carbon number is 30 or less, the compatibility and handleability are excellent.

  Examples of the long-chain alkyl (meth) acrylate (y1) include n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-decyl (meth) acrylate, lauryl (meth) acrylate, and synthetic lauryl (C12 to C13). (Meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, behenyl (meth) acrylate, oleyl (meth) acrylate, myristyl (meth) acrylate, and the like. These may be used alone or in combination of two or more.

  The amount of the long-chain alkyl (meth) acrylate (y1) as a monomer unit contained in the polymer (Y) is preferably 1 to 50% by mass, more preferably 5 to 40% by mass, and 10 to 30% by mass. Is more preferred. When the amount is 1% by mass or more, the surface modification effect by the long-chain alkyl group can be sufficiently obtained. When the amount is 50% by mass or less, the amount of methyl methacrylate does not become relatively small, and compatibility with the polymer (X) can be ensured.

(Macromonomer (y2))
The macromonomer (y2) is a high-molecular-weight monomer (monomer) containing 80% by mass or more of methyl methacrylate as a monomer unit and having a polymerizable unsaturated group at a terminal. When the polymer (Y) contains the macromonomer (y2) as a monomer unit, the polymer (Y) has two conflicting effects of ensuring compatibility with the polymer (X) and improving the surface modification effect. Functions can be provided. By copolymerizing the macromonomer (y2) with the polymer (Y), the macromonomer (y2) has a composition close to that of the polymer (X), so that compatibility can be ensured. Further, in the main chain of the polymer (Y), the density of the long-chain alkyl (meth) acrylate (y1) can be increased, and the surface modification effect can be enhanced. That is, the monomer unit of the macromonomer (y2) plays a role in compatibility, and the main chain containing the monomer unit of the long-chain alkyl (meth) acrylate (y1) plays a role in surface modification, thereby separating functions. be able to.

  The amount of methyl methacrylate as a monomer unit contained in the macromonomer (y2) is 80% by mass or more, preferably 90% by mass or more, and more preferably 95% by mass or more. When the amount is 80% by mass or more, it is easy to ensure compatibility with the polymer (X).

  Further, the macromonomer (y2) may contain a monomer other than methyl methacrylate as a monomer unit. The monomer is preferably the same monomer as the other monomer (x1) contained in the polymer (X) as a monomer unit from the viewpoint of compatibility. Therefore, the monomer is preferably a monofunctional acrylate, and more preferably methyl acrylate.

  The mass average molecular weight (Mw) of the macromonomer (y2) is preferably 1,000 to 1,000,000, more preferably 3,000 to 500,000, still more preferably 5,000 to 300,000. It is particularly preferably from 000 to 50,000 or less. When Mw is 1,000 or more, the physical properties of the molded body tend to be good.

  The amount of the macromonomer (y2) as a monomer unit contained in the polymer (Y) is preferably 1 to 50% by mass, more preferably 10 to 45% by mass, and still more preferably 20 to 40% by mass. When the amount is 50% by mass or less, the amount of the macromonomer (y2) remaining unreacted during the production of the polymer (Y) can be sufficiently suppressed.

(Method for producing macromonomer (y2))
As a method for producing the macromonomer (y2), for example, a method using a cobalt chain transfer agent (U.S. Pat. No. 4,680,352), a method for preparing an α-substituted unsaturated compound such as α-bromomethylstyrene, A method of using as a transfer agent (WO 88 / 04,304), a method of chemically bonding a polymerizable group (JP-A-60-133007 and US Pat. No. 5,147,952), and thermal decomposition (JP-A-11-240854).

  Among these, as the method for producing the macromonomer (y2), a method using a cobalt chain transfer agent is preferable because the number of production steps is small and a catalyst having a high chain transfer constant is used. Examples of the method for producing the macromonomer (y2) using the cobalt chain transfer agent include aqueous dispersion polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization. Among these, an aqueous dispersion polymerization method is preferred from the viewpoint of simplifying the recovery step of the macromonomer (y2).

  Solvents used for obtaining the macromonomer (y2) by the solution polymerization method include, for example, hydrocarbons such as toluene; ethers such as diethyl ether and tetrahydrofuran; halogenated hydrocarbons such as dichloromethane and chloroform; ketones such as acetone. Alcohols such as methanol; nitriles such as acetonitrile; vinyl esters such as ethyl acetate; carbonates such as ethylene carbonate; and supercritical carbon dioxide. These can be used alone or in combination of two or more.

(Other monomer (y3))
The other monomer (y3) is a monomer other than methyl methacrylate, long-chain alkyl (meth) acrylate (y1) and macromonomer (y2), and has copolymerizability with these monomers. Although there is no particular limitation as long as it is present, it is preferable to use a monofunctional acrylate since the thermal decomposition resistance of the polymer (Y) can be improved. By copolymerizing these monomers with a monofunctional acrylate, the depolymerization reaction (zipper cleavage) of polymethyl methacrylate can be prevented.

  Examples of the other monomer (y3) include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, and the like. Among these, methyl acrylate is preferable from the balance between heat resistance and cost. These may be used alone or in combination of two or more.

  As a method for producing the polymer (Y), for example, known methods such as a solution polymerization method, a bulk polymerization method, a suspension polymerization method, an emulsion polymerization method, and a precipitation polymerization method can be used. Among these methods, the bulk polymerization method and the suspension polymerization method are preferable, and the bulk polymerization method is more preferable. The bulk polymerization method is suitable for mass production, and is advantageous in terms of production speed (production amount), production cost, and the like.

  The proportion of the polymer (Y) contained in the acrylic resin molding material is preferably from 1 to 49 parts by mass, more preferably from 2 to 40 parts by mass, based on 100 parts by mass of the polymer (X) and the polymer (Y) in total. Is more preferable, and 5 to 30 parts by mass is further preferable. When the ratio is within the above range, a sufficient surface modification effect can be obtained.

[Other components (Z)]
The acrylic resin molding material according to the present invention can contain other resins and additives as other components (Z) in addition to the polymer (X) and the polymer (Y).

<Other resins>
Other resins are not particularly limited as long as they are other than the polymer (X) and the polymer (Y), and known thermoplastic resins and curable resins can be used.

  Examples of the thermoplastic resin include a polypropylene resin, a polyethylene resin, a polystyrene resin, a syndiotactic polystyrene resin, an ABS (acrylonitrile-butadiene-styrene) resin, an acrylic resin, an AS (acrylonitrile-styrene) resin, and a BAAS (styrene-acrylonitrile- Butyl acrylate) resin, MBS (methyl methacrylate-butadiene-styrene) resin, AAS (acrylonitrile-acrylate-styrene) resin, biodegradable resin, polycarbonate-ABS resin alloy, polybutylene terephthalate, polyethylene terephthalate, polypropylene terephthalate, polytriacrylate Polyalkylene arylate resin such as methylene terephthalate and polyethylene naphthalate, polyamide resin, polyphenylene Ether resins, polyphenylene sulfide resins, phenol resins and the like. Among these, AS resin and BAAS resin are preferable for improving fluidity. Further, ABS resin and MBS resin are preferable for improving impact resistance. Further, polyester resin is preferable for improving chemical resistance. In addition, polyphenylene ether resin, polyphenylene sulfide resin, and phenol resin can be expected to have an effect of improving flame retardancy.

  As the curable resin, for example, unsaturated polyester resin, vinyl ester resin, diallyl phthalate resin, epoxy resin, cyanate resin, xylene resin, triazine resin, urea resin, melamine resin, benzoguanamine resin, urethane resin, oxetane resin, ketone resin Alkyd resin, furan resin, styrylpyridine resin, silicone resin, synthetic rubber and the like. These other resins may be used alone or in combination of two or more.

<Additives>
The acrylic resin molding material according to the present invention can include a predetermined additive in order to impart various properties such as rigidity and dimensional stability. Examples of additives include various stabilizers such as antioxidants, ultraviolet absorbers, heat stabilizers, and light stabilizers; plasticizers (paraffin-based process oil, naphthene-based process oil, aromatic-based process oil, paraffin, organic Polysiloxane, mineral oil, etc.), flame retardants (phosphorus such as organic phosphorus compounds, red phosphorus, inorganic phosphates, halogens, silicas, silicones, etc.), flame retardant assistants (antimony oxides, metal oxidation) Substances, metal hydroxides, etc.), curing agents (diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, diethylaminopropylamine, 3,9-bis (3-aminopropyl) -2,4,8,10 -Tetraoxaspiro [5,5] undecane, mensendiamine, isophoronediamine, N-aminoethylpipe Amines such as gin, m-xylenediamine, m-phenylenediamine, diaminophenylmethane, diaminodiphenylsulfone, dicyandiamide, adipic dihydrazide, phenolic resins such as phenol novolak resin and cresol novolak resin, liquid polymercaptan, and polysulfide and the like. Polymercaptan, maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, pyromellitic anhydride, methylcyclohexenetetracarboxylic anhydride Products, dodecyl succinic anhydride, trimellitic anhydride, chlorendic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bis (anhydrotri Acid anhydrides, etc.), curing accelerators (2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole) , Imidazoles such as 2-phenyl-4-methylimidazole, organic phosphines such as triphenylphosphine and tributylphosphine, benzyldimethylamine, 2-dimethylaminomethylphenol, 2,4,6-tris (diaminomethyl) phenol, Tertiary amines such as tetramethylhexanediamine, boron salts such as triphenylphosphine tetraphenylborate, tetraphenylphosphonium tetraphenylborate and triethylamine tetraphenylborate, 1,4-benzoquinone, and 1,4-naphtho Quinone compounds such as quinone, 2,3-dimethyl-1,4-benzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-1,4-benzoquinone, etc., antistatic agents (polyamide elastomer, quaternary ammonium salt) , Pyridine derivative, aliphatic sulfonate, aromatic sulfonate, aromatic sulfonate copolymer, sulfate, polyhydric alcohol partial ester, alkyldiethanolamine, alkyldiethanolamide, polyalkylene glycol derivative, betaine, Imidazoline derivatives, etc.), conductivity-imparting agents, stress relievers, release agents (alcohols, esters of alcohols and fatty acids, esters of alcohols and dicarboxylic acids, silicone oils, etc.), crystallization promoters, hydrolysis inhibitors, Lubricants (stearic acid, behenic acid, stearic acid Etc.), impact modifiers, compatibilizers, nucleating agents, reinforcing agents, flow regulators, dyes (nitroso dyes, nitro dyes, azo dyes, stilbene azo dyes, ketoimine dyes, triphenylmethane dyes, xanthene dyes, acridine dyes, Quinoline dye, methine / polymethine dye, thiazole dye, indamine / indophenol dye, azine dye, oxazine dye, thiazine dye, sulfur dye, aminoketone / oxyketone dye, anthraquinone dye, indigoid dye, phthalocyanine dye, etc.), sensitizer, coloring Agents (titanium oxide, carbon black, titanium yellow, iron oxide pigments, ultramarine, cobalt blue, chromium oxide, spinel green, lead chromate pigments, inorganic pigments such as cadmium pigments, azo lake pigments, benzimidazolone pigments, diarilides) Pigment, condensed azo face Azo pigments such as phthalocyanine blue, phthalocyanine green, etc., phthalocyanine pigments such as isoindolinone pigments, quinophthalone pigments, quinacridone pigments, perylene pigments, anthraquinone pigments, perinone pigments, condensed polycyclic pigments such as dioxazine violet, etc. Organic pigments, flaky aluminum metallic pigments, spherical aluminum pigments used to improve weld appearance, mica powder for pearlescent metallic pigments, and metal plating on inorganic polyhedral particles such as glass Metallic pigments such as those coated by sputtering, etc.), thickeners, anti-settling agents, anti-sagging agents, fillers (fibrous reinforcing agents such as glass fiber and carbon fiber, glass beads, calcium carbonate, talc, clay, etc.) , Defoamers (silicone defoamers, surfactants, poly Organic antifoaming agents such as ethers and higher alcohols), coupling agents, light diffusing particles, rust inhibitors, antibacterial and antifungal agents, antifouling agents, conductive polymers and the like. These may be used alone or in combination of two or more.

(Light diffusing particles)
Examples of the light diffusing particles include inorganic particles such as alumina, titanium oxide, calcium carbonate, barium sulfate, silicon dioxide, and glass beads; organic styrene-crosslinked beads; MS (methyl methacrylate-styrene) crosslinked beads; and siloxane-based crosslinked beads. And the like. Further, hollow crosslinked particles made of a highly transparent resin material such as an acrylic resin, a polycarbonate resin, an MS resin, a cyclic olefin resin, and the like, and hollow particles made of glass are also included. Among the inorganic particles, inorganic particles of alumina or titanium oxide are preferable. These light diffusing particles can be used alone or in combination.

  The refractive index of the light diffusing particles is preferably 1.7 to 3.0, more preferably 1.7 to 2.5, and even more preferably 1.7 to 2.0. When the refractive index is 1.7 or more, sufficient scattering properties can be obtained. When the refractive index is 3.0 or less, scattering in the vicinity of the lamp is suppressed, and unevenness in brightness and unevenness in color tone of emitted light are less likely to occur. The refractive index is a value at a temperature of 20 ° C. based on the D line (589 nm). As the method of measuring the refractive index, specifically, the light diffusing particles are immersed in a liquid capable of changing the refractive index little by little, and the interface of the light diffusing particles is observed while changing the refractive index of the liquid. Then, the refractive index of the liquid when the interface between the light diffusing particles becomes unclear is measured. Note that an Abbe refractometer is used to measure the refractive index of the liquid.

  The average particle diameter of the light diffusing particles is preferably 0.1 to 20 μm, more preferably 0.2 to 15 μm, further preferably 0.3 to 10 μm, and particularly preferably 0.4 to 5 μm. When the average particle diameter is 20 μm or less, light loss due to back reflection or the like is suppressed, and the incident light can be efficiently diffused to the light emitting surface side. When the average particle diameter is 0.1 μm or more, the emitted light can be diffused, and desired surface emission luminance and diffusivity can be obtained.

  The content of the light-diffusing particles in the acrylic resin molding material according to the present invention is, from the viewpoint of the light diffusion effect and the uniformity of surface light emission, based on 100 parts by mass of the polymer contained in the acrylic resin molding material. 0.0001 to 0.03 parts by mass, more preferably 0.0001 to 0.01 parts by mass.

(Antioxidant)
Examples of the antioxidant include a hindered phenol-based antioxidant and a phosphorus-based antioxidant, and a hindered phenol-based antioxidant is preferable.

  Examples of hindered phenolic antioxidants include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and thiodiethylenebis [3- (3,5-di- tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 3,3 ′, 3 ″, 5,5 ′, 5 ′ '-Hexa-tert-butyl-a, a', a ''-(mesitylene-2,4,6-triyl) tri-p-cresol, 4,6-bis (octylthiomethyl) -o-cresol, , 6-bis (dodecylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy) -M-tolyl) propionate], hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris (3,5-di-tert-butyl) -4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 1,3,5-tris [(4-tert-butyl-3-hydroxy-2 , 6-xylin) methyl] -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di-tert-butyl-4- (4,6-bis ( Octylthio) -1,3,5-triazin-2-ylamine) phenol. Particularly, pentaerythritol terrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] is preferable.

  A commercially available phenolic antioxidant may be used as the hindered phenolic antioxidant. Commercially available phenolic antioxidants include, for example, Irganox 1010 (trade name, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], manufactured by BASF) Irganox 1076 (trade name, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, manufactured by BASF), Irganox 1330 (Irganox 1330, trade name, 3,3) ', 3' ', 5,5', 5 ''-hexa-t-butyl-a, a ', a' '-(mesitylene-2,4,6-triyl) tri-p-cresol, BASF) , Irganox 3114 (trade name, 1,3,5-tris (3,5- -T-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, manufactured by BASF, Irganox 3125 (trade name, manufactured by BASF) ), Sumilizer BHT (Sumilizer BHT, trade name, manufactured by Sumitomo Chemical Co., Ltd.), Cyanox 1790 (Cyanox 1790, trade name, manufactured by Scitech), Sumilizer GA-80 (Sumilizer GA-80, trade name, manufactured by Sumitomo Chemical Co., Ltd.), Sumilizer GS (Sumilizer GS, trade name, manufactured by Sumitomo Chemical), vitamin E (manufactured by Eisai) and the like. Among these, Irganox 1010, Irganox 1076, and Sumilizer GS are preferable. These may be used alone or in combination of two or more.

  Examples of the phosphorus-based antioxidant include tris (2,4-di-t-butylphenyl) phosphite and bis (2,4-bis (1,1-dimethylethyl) -6-methylphenyl) ethyl ester Phosphoric acid, tetrakis (2,4-di-t-butylphenyl) (1,1-biphenyl) -4,4′-diylbisphosphonite, bis (2,4-di-t-butylphenyl) pentaerythritol Diphosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-dicumylphenyl) pentaerythritol-diphosphite, tetrakis (2,4-t- Butylphenyl) (1,1-biphenyl) -4,4′-diylbisphosphonite, di-t-butyl-m-cresyl-phosphonite and the like. It is.

  Further, a commercially available phosphorus-based antioxidant may be used as the phosphorus-based antioxidant. Examples of commercially available phosphorus antioxidants include Irgafos 168 (trade name, Irgafos 168, trade name, tris (2,4-di-t-butylphenyl) phosphite, manufactured by BASF), and Irgafos 12 (trade name, Irgafos 12, trade name). Tris [2-[[2,4,8,10-tetra-t-butyldibenzo [d, f] [1,3,2] dioxaphosphefin-6-yl] oxy] ethyl] amine, BASF ), Irgafos 38 (trade name, bis (2,4-bis (1,1-dimethylethyl) -6-methylphenyl) ethyl ester phosphite, manufactured by BASF), ADEKA STAB 329K (ADEKA STAB 329K, product) Name, made by ADEKA), Adekastab PEP36 (ADEKA STAB PEP36, trade name, ADE A), ADK STAB PEP-8 (ADEKA STAB PEP-8, trade name, manufactured by ADEKA), Sandstab P-EPQ (trade name, manufactured by Clariant), Weston 618 (Weston 618, trade name, manufactured by GE), Weston 619G ( Weston 619G (trade name, manufactured by GE), Ultranox 626 (Ultranox 626, trade name, manufactured by GE), Sumilizer GP (Sumilizer GP, trade name, manufactured by Sumitomo Chemical Co., Ltd.), and the like. These may be used alone or in combination of two or more.

  The amount of the antioxidant is not particularly limited as long as the effect of the present invention can be exhibited. However, from the viewpoint of suppressing bleed-out during molding, the content of the antioxidant in the acrylic resin molding material according to the present invention is 5 parts by mass with respect to 100 parts by mass of the polymer contained in the acrylic resin molding material. Parts by weight, preferably 3 parts by weight or less, more preferably 1 part by weight or less, particularly preferably 0.01 part by weight or more and 0.8 part by weight or less.

(UV absorber)
Examples of the ultraviolet absorber include, for example, benzotriazole compounds, benzotriazine compounds, benzoate compounds, benzophenone compounds, oxybenzophenone compounds, phenol compounds, oxazole compounds, malonic ester compounds, cyanoacrylate compounds Lactone compounds, salicylic acid ester compounds, benzoxazinone compounds, and the like. Among these, benzotriazole-based compounds and benzotriazine-based compounds are preferred. These may be used alone or in combination of two or more.

The ultraviolet absorber preferably has a vapor pressure (P) at 20 ° C. of 1.0 × 10 ⁻⁴ Pa or less, from the viewpoint of ensuring good moldability of the acrylic resin molding material, It is more preferably at most 10 × 10 ⁻⁶ Pa, more preferably at most 1.0 × 10 ⁻⁸ Pa. Here, good moldability means, for example, that a low molecular compound adheres little to a roll when the film is molded. When the low-molecular compound adheres to the roll, the low-molecular compound re-adheres to the surface of the molded body, and thus the appearance may be deteriorated or the optical characteristics may be deteriorated.

  The melting point (Tm) of the ultraviolet absorbent is preferably 80 ° C. or higher, more preferably 100 ° C. or higher, further preferably 130 ° C. or higher, and particularly preferably 160 ° C. or higher.

  The UV absorber preferably has a mass reduction rate of 50% or less, more preferably 30% or less, and more preferably 15% or less, when the temperature is raised to 23 to 260 ° C at a rate of 20 ° C / min. More preferably, it is particularly preferably at most 10%, particularly preferably at most 5%.

  The blending amount of the ultraviolet absorber is not particularly limited as long as the effect of the present invention is exhibited. However, from the viewpoint of suppressing bleed-out during molding, the content of the ultraviolet absorber in the acrylic resin molding material according to the present invention is 5 parts by mass with respect to 100 parts by mass of the polymer contained in the acrylic resin molding material. Parts by weight or less, more preferably 3 parts by weight or less, further preferably 1 part by weight or less, and particularly preferably 0.01 parts by weight or more and 0.8 parts by weight or less.

[Production method of acrylic resin molding material]
When the acrylic resin molding material contains the polymer (X) and the polymer (Y), the following method may be mentioned as a method for producing the acrylic resin molding material.
1) The polymer (X) and the polymer (Y) are separately manufactured and melt-kneaded.
2) A syrup composed of the monomer as the raw material of the polymer (X) and the polymer (Y) is prepared and then polymerized to obtain a mixture of the polymer (X) and the polymer (Y).
3) A syrup composed of the monomer as the raw material of the polymer (Y) and the polymer (X) is prepared and then polymerized to obtain a mixture of the polymer (X) and the polymer (Y).

  In the case of the method 1), the melt-kneading can be performed by a known method. For example, kneading can be performed using a kneading machine such as an extruder, a heating roll, a kneader, a roller mixer, and a Banbury mixer. Among these, kneading with an extruder is preferred in terms of productivity. The kneading temperature may be in accordance with the preferred processing temperature of each component contained in the acrylic resin molding material, and is preferably, for example, 140 to 300 ° C, and more preferably 180 to 280 ° C.

[Polymerization initiator]
In the method for producing an acrylic resin molding material, a polymerization initiator may be used for the purpose of adjusting the degree of polymerization of the polymer to be produced. As the polymerization initiator, when performing a radical polymerization, for example, di-t-butyl peroxide, lauroyl peroxide, stearyl peroxide, benzoyl peroxide, t-butylperoxy neodecaneate, t-butylperoxy Pivalate, dilauroyl peroxide, dicumyl peroxide, t-butylperoxy-2-ethylhexanoate, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, Organic peroxides such as 1-bis (t-butylperoxy) cyclohexane, azobisisobutyronitrile, azobisisovaleronitrile, 1,1-azobis (1-cyclohexanecarbonitrile), 2,2′-azobis -4-methoxy-2,4-azobisisobutyronitrile, 2,2'-a Bis-2,4-dimethylvaleronitrile, etc. azo radical polymerization initiator such as 2,2'-azobis-2-methylbutyronitrile and the like. These may be used alone or in combination of two or more. These radical polymerization initiators and a suitable reducing agent may be used in combination as a redox initiator.

  The polymerization initiator is preferably used in the range of 0 to 1 part by mass based on 100 parts by mass of the total amount of all the monomers to be used, in consideration of the temperature at which the polymerization is performed and the half-life of the polymerization initiator. It can be selected as appropriate. When a bulk polymerization method, a cast polymerization method, a suspension polymerization method, or the like is selected, from the viewpoint of preventing coloring of the polymer, examples of the polymerization initiator include, for example, lauroyl peroxide, a peroxide-based initiator, Noyl peroxide, t-butylperoxy-2-ethylhexanoate and the like can be used. Of these, lauroyl peroxide is preferred. These may be used alone or in combination of two or more.

[Chain transfer agent]
In the method for producing an acrylic resin molding material, a chain transfer agent may be used as long as the object of the present invention is not impaired. The chain transfer agent is added for the purpose of controlling the molecular weight and improving the thermal decomposition resistance by sealing the terminal double bond. Examples of the chain transfer agent include alkyl mercaptans, dimethylacetamide, dimethylformamide, triethylamine and the like. Among these chain transfer agents, it is preferable to use alkyl mercaptans from the viewpoint of handleability and stability. Examples of the alkyl mercaptans include, for example, n-butyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-tetradecyl mercaptan, n-octadecyl mercaptan, 2-ethylhexyl thioglycolate, ethylene glycol dithioglycolate Rate, trimethylolpropane tris (thioglycolate), pentaerythritol tetrakis (thioglycolate) and the like. These may be used alone or in combination of two or more. These chain transfer agents can be appropriately added according to the required molecular weight. For example, the chain transfer agent is used in the range of 0.001 to 3 parts by mass with respect to 100 parts by mass of the total amount of all the monomers used. Can be.

[Method of manufacturing molded article]
The molded article according to the present invention is obtained by molding the acrylic resin molding material according to the present invention. Examples of the molding method include injection molding, sheet molding, blow molding, injection blow molding, inflation molding, T-die molding, press molding, extrusion molding, foam molding, and film molding by a casting method. Further, secondary processing molding methods such as pressure forming and vacuum molding can also be used.

  Further, when the acrylic resin molding material contains a curable resin as another resin, after mixing the raw materials of the acrylic resin molding material without solvent, or using a solvent that can be uniformly mixed as necessary, After removing the solvent to obtain an acrylic resin molding material, it is cast into a mold, cured, cooled, and removed from the mold to obtain a molded article. Alternatively, the acrylic resin molding material can be cast into a mold and cured by hot pressing. As the solvent for dissolving the raw materials, those which can uniformly mix various materials and which do not impair the effects of the present invention by use can be used. As the solvent, for example, toluene, xylene, acetone, methyl ethyl ketone, methyl butyl ketone, diethyl ketone, cyclopentanone, cyclohexanone, dimethylformamide, methyl cellosolve, methanol, ethanol, n-propanol, iso-propanol, n-butanol, n-Pentanol, n-hexanol, cyclohexanol, n-hexane, n-pentane and the like. These may be used alone or in combination of two or more.

  Also, a method of kneading and manufacturing an acrylic resin molding material using a kneading machine such as a heating roll, kneader, Banbury mixer, extruder, etc., followed by cooling, pulverization, and further molding by transfer molding, injection molding, compression molding and the like. Can also be used. Examples of the curing method include thermal curing, light curing, UV curing, curing by pressure, and curing by moisture. The order in which the components are mixed can be appropriately selected so that the effects of the present invention can be achieved.

[Use]
The molded article according to the present invention includes, for example, household goods, OA equipment, AV equipment, battery electric equipment use, lighting equipment, housing use, sanitary use, elastic play equipment use, headlamp cover, rear lamp cover, rear combination lamp cover, visor, Vehicle parts such as bag guards, instrument covers, and meter panels, liquid crystal displays, plasma displays, organic EL displays, field emission displays, light guide plates used in displays such as rear projection televisions, diffusion plates, polarizing plate protective films, It can be suitably used for a wave plate, a half-wave plate, a viewing angle control film, a retardation film such as a liquid crystal optical compensation film, a display front plate, a display substrate, a lens, a touch panel, a transparent substrate used for a solar cell, and the like. . In addition, the molded article can be used for a waveguide, a lens, an optical fiber, a coating material of an optical fiber, a lens of an LED, a lens cover, and the like in the fields of an optical communication system, an optical switching system, and an optical measurement system. Further, the molded body can be used as a modifier for other resins.

  Hereinafter, the present invention will be described with reference to specific examples and comparative examples, but the present invention is not limited to these examples.

(Reciprocating friction test)
The measurement of the dynamic friction coefficient by the reciprocating friction test was performed under the following conditions.
Apparatus: HEiDON HHS2000 (trade name, manufactured by Shinto Kagaku)
Analysis software: Tribosoft (product name, manufactured by Shinto Kagaku)
Measuring mode: Constant load reciprocating measurement Moving distance: 30mm
Moving speed: 50 mm / sec Constant load: 2.45 N (250 gf)
Sampling cycle: 10ms
Slider: Double-sided tape (manufactured by Nichiban Co., trade name: Nystack, 20 mm width) on a curved surface corresponding to a spherical surface having a radius of 200 mm or more and 300 mm or less, gold width (manufactured by Toyobo, 100% cotton, color) Name: Sarashi, product name: 6570) in a size of 2 cm square.
-Calculation of the maximum value of the dynamic friction coefficient The maximum value of the dynamic friction coefficient was the value of the dynamic friction coefficient which was the highest between the 10th and 400th reciprocations. In the range of 0 to 9 times where the number of reciprocations is small, the slider and the surface of the test piece are gradually adapted to each other, and the dynamic friction coefficient is not stable. Further, in order to clarify the change in the scratch resistance performance during long-term use, the number of reciprocations was set to 400 as the upper limit.

(Internal haze)
The internal haze is determined by removing the external haze caused by the surface shape from the entire haze of the molded body. The internal haze in the present invention is calculated by assuming that the internal haze of PMMA (manufactured by Mitsubishi Rayon Co., Ltd., product name: VH001) is zero, and calculating the difference in haze from a molded article produced by the same method as in this example. I asked for it. The haze was measured with a D65 light source using a haze meter (manufactured by Nippon Denshoku KK, product name: NDH2000) according to JIS K7165: 1981.

(Arithmetic average roughness Ra)
According to JIS B0601: 2001, the arithmetic average roughness Ra of the surface of the molded body was evaluated using a laser microscope (manufactured by Keyence Corporation, product name: VK-X100). Specifically, the arithmetic average roughness Ra was determined using a 10 × objective lens and using the entire imaging area.

(Martens hardness)
In the present invention, numerical values measured under the following conditions were treated as Martens hardness.
Apparatus: FISCHERSCOPE HM2000 (trade name, manufactured by Helmut Fischer, micro hardness tester)
Indenter: Vickers indenter (four-sided diamond cone)
Evaluation program: [Push (100 mN / 5 sec)] → [Creep (100 mN / 5 sec)] → [Unload (100 mN / 5 sec)].

(Vicat softening temperature (VST))
Based on JIS K7206: 1999, the Vicat softening temperature was measured using a fully automatic heat distortion tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd., product name: No. 148-HDA). Using a micro-kneading injection molding machine (manufactured by Imoto Seisakusho Co., Ltd., product name: 18D7), an acrylic resin molding material was injected at 240 ° C. to produce a test piece having a thickness of 2 mm, which was used for measurement. .

(material)
The raw materials used in Examples and Comparative Examples are shown below.
・ Methyl methacrylate (MMA): Acryester M (trade name) manufactured by Mitsubishi Rayon Co., Ltd.
-Methyl acrylate (MA): manufactured by Mitsubishi Chemical Corporation-Lauryl acrylate (LA): manufactured by Osaka Organic Chemical Industry Co., Ltd.-2,2'-azobisisobutyronitrile (V-60 (AIBN)): Wako Pure Chemical Industries 2,2'-Azobis (2-methylbutyronitrile) (AMBN): Otsuka Chemical Co., Ltd. 1-Octanethiol: Wako Pure Chemical Industries, Ltd. Sodium sulfate: Wako Pure Chemical Industries, Ltd. Methacrylic acid 2 -Sulfoethyl sodium: Acryester SEM-Na (trade name) manufactured by Mitsubishi Rayon Co., Ltd.
2,2'-azobis (2-methylpropionamidine) dihydrochloride (V-50): manufactured by Wako Pure Chemical Industries, Ltd.Cobalt acetate (II) tetrahydrate: manufactured by Wako Pure Chemical Industries, special grade of Wako Diphenylglyoxime: manufactured by Tokyo Chemical Industry Co., Ltd., EP grade, boron trifluoride diethyl ether complex: manufactured by Tokyo Chemical Industry Co., Ltd., EP grade, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate ( Perocta O): manufactured by NOF Corporation.

(Measurement of Mw and Mn)
Mw and Mn of the polymer were measured using gel permeation chromatography (GPC) (trade name: HLC-8220, manufactured by Tosoh Corporation) under the following conditions.
Column: TSK GUARD cobalt LUMN SUPER HZ-L (4.6 × 35 mm) and two TSK-GEL SUPER HZM-N (6.0 × 150 mm) connected in series Eluent: Tetrahydrofuran Measurement temperature: 40 ° C.
Flow rate: 0.6 mL / min Mw and Mn of the polymer were PMMA (Mp (peak top molecular weight) = 141,500, 55,600, 10,290 and 1,590) manufactured by Polymer Laboratories. It was determined using a calibration curve created using the above.

[Production Example 1] Synthesis of dispersant (1) In a 1200-L reaction vessel equipped with a stirrer, a cooling pipe, and a thermometer, 61.6 parts by mass of a 17% by mass aqueous potassium hydroxide solution and 19.1 parts by weight of MMA were used. Parts by weight and 19.3 parts by weight of deionized water were charged. Next, the solution in the reactor was stirred at room temperature, and after confirming the exothermic peak, the solution was further stirred for 4 hours. Thereafter, the reaction solution in the reactor was cooled to room temperature to obtain an aqueous solution of potassium methacrylate. Next, 900 parts by mass of deionized water, 60 parts by mass of acrylester SEM-Na, and 10 parts by mass of the aqueous solution of potassium methacrylate were placed in a 1,050 L reaction vessel equipped with a stirrer, a cooling pipe, and a thermometer. And 12 parts by mass of MMA were added and stirred, and the temperature was raised to 50 ° C. while replacing the inside of the polymerization apparatus with nitrogen. Therein, 0.08 part of V-50 was added as a polymerization initiator, and the temperature was further raised to 60 ° C. After the temperature was raised, MMA was continuously dropped for 75 minutes at a rate of 0.24 parts / minute using a dropping pump. After maintaining the reaction solution at 60 ° C. for 6 hours, it was cooled to room temperature to obtain a dispersant (1) having a solid content of 10% by mass as a transparent aqueous solution.

[Production Example 2] Synthesis of cobalt complex (1) In a synthesizer equipped with a stirrer, 2.00 g (8.03 mmol) of cobalt acetate (II) tetrahydrate and 3 parts of diphenylglyoxime were placed under a nitrogen atmosphere. .86 g (16.1 mmol) and 100 ml of diethyl ether previously deoxygenated by bubbling with nitrogen were added, and the mixture was stirred at room temperature for 2 hours. Next, 20 ml of boron trifluoride diethyl ether complex was added, and the mixture was further stirred for 6 hours. The obtained product was filtered, and the solid was washed with diethyl ether. Thereafter, this was dried at 100 ° C. or less at 20 ° C. for 12 hours to obtain 5.02 g (7.93 mmol, yield: 99% by mass) of a cobalt complex (1) as a brown solid.

[Production Example 3] Synthesis of macromonomer (y2-1) In a polymerization apparatus equipped with a stirrer, a cooling pipe, and a thermometer, 145 parts by mass of deionized water, 0.1 part by mass of sodium sulfate, and Production Example 0.26 parts by mass of the dispersant (1) (solid content 10% by mass) produced in 1 was added and stirred to obtain a uniform aqueous solution. Next, 95 parts by mass of methyl methacrylate, 5 parts by mass of methyl acrylate, 0.0016 parts by mass of the cobalt complex (1) produced in Production Example 2, and 0.1 part by mass of perocta O as a polymerization initiator were added, An aqueous dispersion was obtained. Next, the inside of the polymerization apparatus was sufficiently purged with nitrogen, and the aqueous dispersion was heated to 80 ° C., kept for 4 hours, and then heated to 92 ° C. and kept for 2 hours. Thereafter, the reaction solution was cooled to 40 ° C. to obtain an aqueous suspension of a macromonomer. The aqueous suspension of macromonomer was filtered through a filter cloth and the filtrate was washed with deionized water. Thereafter, this was dried at 40 ° C. for 16 hours to obtain a macromonomer (y2-1). Mw of the macromonomer (y2-1) was 29,000 and Mn was 15,000. Table 1 shows the composition, Mw, Mn, and Mw / Mn of the macromonomer (y2-1).

[Production Example 4] Synthesis of polymer (X-1) 150 parts by mass of deionized water, 0.3 parts by mass of sodium sulfate, and 0.26 parts by mass of dispersant (1) produced in Production Example 1 were mixed. An aqueous dispersion medium for suspension was prepared. In a separable flask equipped with a cooling tube, 99 parts by mass of MMA, 1 part by mass of MA, 0.2 parts by mass of n-octanethiol as a chain transfer agent, and 0.1 parts by mass of AIBN are charged and stirred to obtain a uniform raw material. A composition was obtained. Next, after the aqueous dispersion medium for suspension was added to the raw material composition, a syrup dispersion liquid was obtained by increasing the stirring rotation speed while replacing the atmosphere in the separable flask with nitrogen by bubbling with nitrogen. The temperature of the syrup dispersion was raised to 75 ° C., and the external temperature of the separable flask was maintained. After the polymerization exothermic peak appeared, when the temperature of the syrup dispersion reached 75 ° C., the temperature of the syrup dispersion was raised to 85 ° C. and maintained for 30 minutes to complete the polymerization to obtain a suspension. After the suspension was cooled to 40 ° C. or lower, the suspension was filtered with a filter cloth, and the filtrate was washed with deionized water and dried at 40 ° C. for 16 hours to obtain a polymer (X-1). I got Mw of the polymer (X-1) was 86,000, and Mn was 47,000. Table 1 shows the composition, Mw, Mn, and Mw / Mn of the polymer (X-1).

[Production Example 5] Synthesis of polymer (Y-1) 150 parts by mass of deionized water, 0.3 parts by mass of sodium sulfate, and 0.26 parts by mass of dispersant (1) produced in Production Example 1 were mixed. An aqueous dispersion medium for suspension was prepared. 80 parts by mass of MMA, 20 parts by mass of LA, 0.2 parts by mass of n-octanethiol as a chain transfer agent, and 0.1 parts by mass of AIBN were charged into a separable flask equipped with a cooling tube, and stirred to obtain a uniform raw material. A composition was obtained. Next, after the aqueous dispersion medium for suspension was added to the raw material composition, a syrup dispersion liquid was obtained by increasing the stirring rotation speed while replacing the atmosphere in the separable flask with nitrogen by bubbling with nitrogen. The temperature of the syrup dispersion was raised to 75 ° C., and the external temperature of the separable flask was maintained. After the polymerization exothermic peak appeared, when the temperature of the syrup dispersion reached 75 ° C., the temperature of the syrup dispersion was raised to 85 ° C. and maintained for 30 minutes to complete the polymerization to obtain a suspension. After the suspension was cooled to 40 ° C. or lower, the suspension was filtered with a filter cloth, and the filtrate was washed with deionized water and dried at 40 ° C. for 16 hours to obtain a polymer (Y-1). I got Mw of the polymer (Y-1) was 126,000 and Mn was 70,000. Table 1 shows the composition, Mw, Mn, and Mw / Mn of the polymer (Y-1).

[Production Example 6] Synthesis of Polymer (Y-2) 145 parts by mass of deionized water, 0.1 part by mass of sodium sulfate, and 0.26 parts by mass of dispersant (1) produced in Production Example 1 were mixed. An aqueous dispersion medium for suspension was prepared. In a separable flask with a condenser, 40 parts by mass of the macromonomer (y2-1), 40 parts by mass of MMA, 20 parts by mass of LA, and 0.1 part by mass of n-octanethiol as a chain transfer agent were stirred and stirred. While heating to 50 ° C., a composition in a syrup state was obtained. After the composition was cooled to 40 ° C. or lower, 0.3 parts by mass of AMBN was dissolved in the composition to obtain a raw material composition. Next, after the aqueous dispersion medium for suspension was added to the raw material composition, a syrup dispersion liquid was obtained by increasing the stirring rotation speed while replacing the atmosphere in the separable flask with nitrogen by bubbling with nitrogen. The temperature of the syrup dispersion was raised to 75 ° C., and the external temperature of the separable flask was maintained. After the polymerization exothermic peak appeared, when the temperature of the syrup dispersion reached 75 ° C., the temperature of the syrup dispersion was raised to 85 ° C. and maintained for 30 minutes to complete the polymerization to obtain a suspension. After the suspension was cooled to 40 ° C. or lower, the suspension was filtered with a filter cloth, and the filtrate was washed with deionized water and dried at 40 ° C. for 16 hours to obtain a polymer (Y-2). I got Mw of the polymer (Y-2) was 93,000 and Mn was 33,000. Table 1 shows the composition, Mw, Mn, and Mw / Mn of the polymer (Y-2).

[Example 1]
Using a Labo Plastomill (manufactured by Toyo Seiki), 90 parts by mass of the polymer (X-1) obtained in Production Example 4 and 10 parts by mass of the polymer (Y-1) obtained in Production Example 5 were melt-kneaded. (At 230 ° C., 10 minutes, 30 rpm) to obtain an acrylic resin molding material.

  Using a 0.5 mm thick spacer made of PTFE (polytetrafluoroethylene), 2 g of a powdery acrylic resin molding material was sandwiched between two mirror-finished iron plates having a thickness of 2 mm. Then, using a hot press machine (manufactured by Toyo Seiki Co., Ltd., product name: Mini Test Press), preheating at a temperature of 200 ° C. for 3 minutes, followed by pressing at a pressure of 1 MPa for 3 minutes to form a 0.5 mm thick sheet. I got a body.

  The acrylic resin molding material and the molded article were evaluated by the above method. Table 2 shows the results.

[Example 2, Comparative Examples 1-4]
The procedure was performed in the same manner as in Example 1, except that the composition and the mixing ratio of the acrylic resin molding material were changed to the contents shown in Table 2. In Comparative Example 2, 5.0 parts by mass of Nofaalloy KA832 (trade name, manufactured by NOF CORPORATION) was added as a scratch resistance improving aid. Table 2 shows the results.

   In Example 1, the maximum value of the coefficient of kinetic friction between the 10th and 400th reciprocations was 0.33, indicating that sufficient slipperiness was exhibited and the scratch resistance was good. Further, the internal haze value was 0.2%, and it was found that the film had high transparency. Further, it was found that the Martens hardness and the Vicat softening temperature maintained almost the same performance as in Comparative Example 1 using PMMA. Therefore, in Example 1, it was found that the dynamic friction coefficient of the surface was reduced while maintaining the transparency, hardness and heat resistance of PMMA.

  In Example 2, the polymer (Y) in Example 1 was changed from the polymer (Y-1) to the polymer (Y-2). However, as in Example 1, the polymer (Y) had a sufficiently low dynamic friction coefficient. It was confirmed that the scratch resistance was good. In addition, the internal haze value was 0.1%, indicating that the film had high transparency.

  In Comparative Example 1, the polymer (Y) was not contained, and the coefficient of kinetic friction always exceeded 0.4 in the reciprocating friction test, indicating that the surface was more easily damaged than the Examples.

  In Comparative Example 2, Nofaalloy KA832 (trade name, manufactured by NOF CORPORATION) was added as an abrasion resistance improving aid instead of the polymer (Y). However, although the dynamic friction coefficient was low and the abrasion resistance was improved, the internal The haze value was 37.8%, and the molded product was cloudy. Further, the Martens hardness and the Vicat softening temperature were also lower than those of the examples.

  In Comparative Example 3, only the polymer (Y-1) was used without using the polymer (X). However, the molded article was too soft and easily damaged, and the dynamic friction coefficient was increased.

  In Comparative Example 4, the mass ratio between the polymer (X-1) and the polymer (Y-2) was changed to 50/50 in Example 2, but the molded article became too soft and easily damaged, and the dynamic friction was increased. Coefficient increased.

  Since the molded article according to the present invention has excellent scratch resistance and transparency, it can be used as a molded article for a vehicle exterior, a molded article for sanitary use such as a washbasin or a toilet.

Claims (5)

Polymers containing more than 80 wt% of methyl methacrylate as a monomer unit (X) (as monomer units, except those carbon atoms containing an alkyl (meth) acrylate having 8 to 30 alkyl group) When,
As monomer units, methyl methacrylate, polymers containing, alkyl (meth) acrylate having an alkyl group with a carbon number of 8 to 30 and (Y),
The A molded article comprising including an acrylic resin molding material,
The proportion of the polymer (X) is 60 to 98 parts by mass with respect to a total of 100 parts by mass of the polymer (X) and the polymer (Y),
Without having a coating layer having a thickness of 1 μm or more on the surface of the molded body,
When a reciprocating friction test was performed using a cotton cloth as a slider at a constant load of 2.45 N (250 gf) on the surface of the molded body, the maximum value of the coefficient of dynamic friction was 0.4 or less within the range of 10 to 400 reciprocations. And a molded article having an internal haze value of 2.5% or less. Molded body according to claim 1 Martens hardness of the surface of the molded body is 140~250N / mm ^2.   The molded article according to claim 1, wherein the acrylic resin molding material has a Vicat softening temperature of 108 ° C. or higher.   The molded body according to any one of claims 1 to 3, wherein an arithmetic average roughness Ra of the surface of the molded body is 5.0 or less. The amount of methyl methacrylate as a monomer unit contained in the polymer (Y) is from 60 to 90% by mass,
The molded article according to any one of claims 1 to 4 , wherein the amount of the alkyl (meth) acrylate as a monomer unit contained in the polymer (Y) is 5 to 40% by mass.